Arc-light electrode.



l. LADOFF.

ARC LIGHT ELECTRODE.

APPLICATION FILED Nov.27.191|.

Patented Dec. 21, 1915.

IISOR LADOFIE, 01E CLEVELAND, OHIO, SSIGNOR, BY MESNE ASSIGNMENTS, 0F y THIRTY UNE-HUNDREDTHS T0 WALTER D. EDMONDS, 0F BOONVILLE, NEW

YORK.

Anc-LIGHT nLncrRonn ideata..

Specication of Letters Patent.

Patented Meer., 21, tml...

To all whom it may concern: Be it known `that I, IsAnoR LADOFF, a citizen'of the United States, and a resident ofy Cleveland, in the county of Cuyahoga and State of `Ohio, have invented certain new and useful Improvements in Arc-Light Electrodes, of which the following is a specification, v

My present invention relates to so-called a'ming arc electrodes of the type composed essentially of so-called mineralized carbon, these being, loosely speaking, electrodes composed largely, in fact usually preponderatingly, of carbon with which has been associated various mineral substances to increase candle-power efficiency, etc.,such association imparting, to an extent, tothe resulting arc the said laming. and other characteristics incidental to electrodes coinposed principally of metallic substances vas distinguished from carbon. rfothese ends have been hitherto associated with the constituent carbon of the electrode various compounds of metallic character, for example calcium salts, particularly calcium fluorid, which, thoughl increasing intensity of light, has proved unsatisfactory owing to its giving a reddish color to the arc, especially when the wattage drops below a certain minimum as is unavoidable in commercial installations. To overcome such defects resort has also been had, with more or less indi'erent success, to additions to the calcium of other fluorids, e. g. sodium iiuorids, also borates, rare earths, carbids of boron and of titanium, and even titanium oXid. 'lEven tungstate ofcalcium has been tried as a substitute for the Icalcium fluorid or part of it, though this has the disadvantage of being reduced in the arc to metallic tungsten which rectiiies the current. But the flaming arcs from the types of electrodes mentioned have hitherto been characterized by undesirable flickering and changes `in color.

Prior to my present. inventionsand those described in my herewith co-pending application, Serial Number 630,545, filed J une 1,

1911, the only titanium compound found serviceable for the purpose mentioned on alternating current lines has been, so far las l know, titanium carbid, but this substance, owing to its instability, has proved also undesirable, breaking up in the arc stream into carbon which too quickly burns away and titanium which too rapidly` oxidizes.

The object of my present invention is to provide means whereby mineralized carbon electrodes giving flaming arcs ma without impairing their operativeness 1n alternating currents, develop more eiiicient, steady, and whiter arcs than heretofore. This object l attain by my improvements as hereinafter described.

My researches have now. demonstrated that the mineral additions heretofore made by othersto the carbon as heretofore noted cause the electrodes to behave unsatisfactorily inthe particulars mentioned largely because of insufiicient homogeneity and harmoniousness of behavior and action as,

regards the physical, chemical, and lightgiving properties of the constitutin ingredients, and also because of undesirable colors imparted to the arc by such additions. l have now discovered that certain chemical compounds of titanium with certain metals give a substantially white light in the arc and possess such properties as to realize the said objects of my invention, when incorporated into said mineralized carbon electrodes. Any proportion of such compounds so incorporated will produce, proportionally, the beneficial effects referred to, but for industrial purposes I find it preferable to incorporate, as hereinafter noted, av substantial amount of such compound or compounds sufficient to secure the maximum desired effeet thereof'without unduly impairing those well-known characteristics and behaviors of the electrode which are attributable to its preferably predominating carbon content. As examples of said compounds of titanium with metals, l have found satisfactory for said purpose titanates of the following inetals, viz z-Titanate of barium (3'l`iU2Ba), titanate lof aluminum (Al'lliOg), titanate of magnesium (Mg'lliOa), titanate of cerium (Ce'lFiO,), v fand titanate of thorium (ThTiOa), each of said compounds giving eej a substantially white lightgin the arc. My v ica ` manufacture or use. Ihave also found that with 1439 parts of powdered calcined carl employed other than titanium, halogilxes mixed with a binder and sufficiently `convenience, it is impossible to predicate anycent. of the whole electrode.

a vcompound of titanium with the metalloid bon. To this mixture I have imparted the boron, to wit, borate of titanium (BQTIQV) coherence of stiff paste, by adding thereto behaves similarly and with substantially and mixing therewith a suitable binder such equally good results as said titanates, said as tar or a solution of sugar. The resulting compound, like theothers mentioned, giving product was then applied in the well known a white or substantially white light 1n the manner as'coring material to fill the bores of arc. usual electrode skeletons composed of pure As above indicated, it is preferable, if not carbon and the so cored electrodes dried at always essential, inasmuch as the compounds 200 to 300 C. to constitute one form of 75 mentioned are more or less refractory, to asmy Said IIIDI'OVed electrode.

sociate therewith, in the electrode, according ven more perfect homogeneity'may be to the special requirements of ach, as desecured, and I prefer this in every lnstance, termined by the character, an the surby preliminarily-fusing the aforesaid mixrounding conditions, of the particular titanture of barium tltanate and other minerals ate employed, an additional substance, or into a; completely homogeneous mass. Sain substances, primarily for the purpose of act- IMSS 1S then DlllVeFlZed 111 any COIIVGIIIQII ing aS illXeS during arcing. Such Submanner, the resulting powder thoroughly stances should be selected with a view to mXed Wlth DO Wdelef Cal'bOn, COhEIence irntheir imparting the least possible of undeparted by IIllXlIlg Wlth any Suitable blnder, sirable color, or of dimness, to the arc. To the bores of the skeleton electrode filled with this end I employ Such quantities of such the resulting product and the whole dried as flux or` iuxes as convenience or testmay, in before.

each case, determine to be best adapted for It will be understood that my electrode the purposes required. I have found suitmay, though unpreferably, be composed enable for this purpose iuorids'of thealkali trely of my mixture comprising as aforemetals, luorids of the metal .of the titanate said, barium titanate and suitable mineral pounds of titanium, rare earths such a oxid dried, or even .fused together or treated in of cerium or oxid of thorium, etc., the e a y other well known way to impart there- 0f such fluxes being accessory to my present;` to requisite mechanical strength, but in such invention which, in its broadest aspects, concase the proportion of carbon content should sists in utilization, in arc electrodes, as be increased so as to constitute a preponderaforesaid, of chemical compounds of tita- ,ance of carbonin the electrode. In fact I nium with metals, which compounds give prefer that the carbon should constitute in a substantially white light in the arc. the neighborhood of two-thirds of the elec- Inasmuch as the extent and nature of the trode taken as a whole. The total percentfluxesreferred tomay be more or less varied age of carbon which I deem most satisfacin each case according to circumstances, or tory in results is from 70 per cent; to 60 per hard and fast rules for their use which with- It will be understood that my electrode,

. in the limits aforesaid will be readily dein cases in which titanates of metals giving produce, preliminarily, an intimate homo,-

Aforegoing and the examples of kind and.` other titanates, or the borate of titanium proportion hereinafter given..

termined by those skilled in the art, without a white .light to the arc other than barium further information than imparted by the titanate are employed, as for instance the l above referred to, are produced in substanhe superior eiciency and otherdesired tially the same manner and proportions and qualities of my electrodes are, I believe, atassociated with the same fluxes as in the case tributable not only to their novel ingredients of barium titanate, the only substantial difas above stated, but also to my manner of ference in procedure being that the titanate associating these with each other and with ofthe particular metal employed is substicarbon in the electrode whereby homo-y tuted for the barium titanate and prefergeneity is increased. I therefore prefer to ably the fluorid of said metal for the barium fluorid, but, as aforesaid, it will be ungeneous cohesive mixture of the'said ingrederstood that other fluxes than those ,enu- 12o dients as follows :J-I have, for example, in merated in the foregoing example may be,

a case in which barium titanate was. emin whole or in part, employed without deployed as aforesaid, taken' by weight of parting from my invention.

barium titanate (3TiO2,2Ba) 170 parts, of Referring to the accompanying drawings, barium iiuorid (BaFlz) 100 parts, of cerium Figure 1 is a view partly in elevation and 125 oxid (CeO) 100 parts, pf potassium titanopartly in central longitudinal section of one fluorid (KTiFl) 48 parts, of thorium oxid form of my electrode; Fig. 2 a transverse (ThO2) 2 parts, of sodium fluorid (NaFl) section on line 2-2 of Fig. 1; Fig. 3 a view 100 parts. These ingredients being finely similar to Fig. 1 of another form of my elecpowdred,Ihave thoroughly mixed together trode; Fig. 4 a transverse vsection on line 130 amara@ a--l of lFig. ligs. 5 and 6 similar views of another form of my electrode.

Similar reference characters indicate similar parts. v

a indicates my aforesaid homogeneous mixture comprising one of the titanates speciied,carbon and a suitable flux.

b indicates the shell of carbon, constituting the skeleton above referred to, which is,

in this instance, of cylindrical type having itsbore cored with my said mixture a, c indicates another type of carbon skeleton multi-bored and multi-cored With my said mixture.

In the claims Where mention is made of a metal which gives a substantially white light in the arc, it will be understood that metalloids which give a substantially White light in the arc, as hereinbefore explained, l

are embodied Within the scope of the claims. Having thus described my invention, what l claim as new and desire to seelre by lietters Patent is the following, viz

l. An arc light lelectrode comprising a preponderance of carbon, and a titanate of 25 a non-ferruginous metal which gives a substantially White light in the arc,

2, An are' light electrode comprising at least sixty per cent. of carbon, and a titanate `of a non-ferruginous metal which gives a substantially White light in the are. A

3. An are light electrode comprising a\pre ponderance of carbon, and a titanate of barium.

4. An arc light electrode comprising at least sixty per cent; of carbon, and a titanate of barium.

ISADR LADOFF.

Witnesses:

H. M. MGKOUGH, Ml. C. BIxlY. 

